1. Field of the Invention
This invention relates to gripping devices.
More particularly, the present invention relates to gripping apparatus of the general type having a pair of opposed gripping members and typically fitted to a refuse collection vehicle.
In a further and more specific aspect, the instant invention concerns an improved gripping apparatus especially adapted for alternately engaging and holding multifarious refuse containers.
2. Prior Art
The collection and disposition of refuse, common commercial and domestic waste and trash colloquially referred to as garbage, has become highly sophisticated, mechanized and automated. Initially, the refuse is deposited and temporarily stored in a conveniently located container. Subsequently, the contents of the container are received by a refuse collection vehicle for ultimate transfer to a disposal site. The vehicle, usually operating on a regular periodic schedule, is generally capable of accommodating numerous containers.
Refuse containers for the instant purpose are readily commercially available in an array of types, sizes and configurations. Common, for example, are stationary containers and portable containers, large containers and small containers, and round containers and square containers. Large round containers, usually permanently positioned at a central location for multiple users, have a capacity ranging to four hundred gallons and a diameter as large as forty-eight inches. Having capacities beginning at approximately thirty gallons and diameters of fifteen inches, small round containers are frequently fitted with wheels for mobility. Square containers, with a transverse measurement in the range of fourteen inches to twenty-nine inches, have a nominal capacity of forty to ninety gallons.
The foregoing measurements and geometric configurations are taken in cross-section at the gripping surface or perimeter which resides approximately twenty-eight inches above the supporting surface. In actuality, each container is defined by a continuous, upright sidewall having a taper in the general range of four to seven degrees which accommodates mold release and stacking. Preferably fabricated of polyethylene by various conventional molding processes, the typical container is characterized by a relatively flexible sidewall having a substantially smooth exterior surface.
The conventional refuse collection vehicle basically includes a cab, a body and a container handling mechanism carried upon a wheeled chassis. The container handling mechanism is controllably actuated in response to an on-board source of pressurized hydraulic fluid selectively directed by controls located at the operator's compartment within the cab. The body is generally bipartite, having a hopper and a stowage bin for respectively receiving and stowing refuse. Refuse handling means, usually termed a packer, transfers and compacts refuse from the hopper to the stowage bin.
Typically, the container handling mechanism includes a pair of opposed gripping members carried at the end of a lifting member or boom which is extendable and retractable relative the curb or pick-up side of the vehicle. During travel of the vehicle, the container handling mechanism resides in a retracted position with the gripping members extending in opposite directions, fore and aft, along the side of the vehicle. After the vehicle is brought to a stop, the boom is extended and the gripping members engaged about the container. The boom is then elevated to position the container atilt over the hopper for deposit of the refuse. Successively, the boom is lowered, the container released and the container handling mechanism retracted for stowage during subsequent movement of the vehicle.
The interaction between the container and the container handling mechanism is rife with inherent problems. Initially noted is the engagement of the gripping members which is primarily dependent upon the forces of constriction and friction to lift, tilt and maneuver the container. Insufficient force will result in the container slipping from the grasp of the gripping members, especially during tilting with a resultant fall into the hopper. Conversely, a container is easily subjected to destructive distortion by excessive or improperly applied force.
Another source of considerable concern is the fact that a random, homogeneous mix of containers are frequently utilized within a given geographic area. Conventional prior art gripping members are generally limited to engaging and holding a specifically designated container. Accordingly, the area must be traversed by more than one collection vehicle, or alternately, by a single vehicle on successive trips following alteration of the gripping apparatus.
Various other sources of perturbation are also evident. For example, initial overextension of the boom can tip or push the container beyond reach of the gripping members. Correction is laborious and wasteful. Further noteworthy is the retracted position of container handling apparatus. The exceedingly long gripping members, extending fore and aft, must either reside precariously outboard of the wheels, beyond the legal envelope width, or require a vehicle of considerable wheelbase.
The prior art has proposed various purported solutions to the foregoing problems. However, none has proven to be entirely satisfactory. It would be highly desirable, therefore, to remedy the foregoing and other deficiencies inherent in the prior art.
Accordingly, it is an object of the present invention to provide an improved gripping apparatus of the type normally used in connection with a refuse collection vehicle.
Another object of the invention is the provision of an improved gripping apparatus especially adapted for engaging and holding refuse containers of diverse cross-sectional configuration and measurement.
And another object of this invention is to provide a gripping apparatus which, without modification or alteration, can alternately grip a variety of containers.
Still another object of the invention is the provision of means for securely gripping a wide variety of containers with minimal distortion.
Yet another object of this instant invention is to provide a gripping apparatus having improved means for relatively uniformly distributing the gripping load about the perimeter of a container.
Yet still another object of the invention is the provision of an improved gripping apparatus for applying a generally circumferential compressive gripping force to a refuse container.
A further object of the invention is to provide a gripping apparatus having novel means for extending about and pulling a container into an ameliorated gripping position.
And a further object of the immediate invention is the provision of a gripping apparatus which is more compactly stowable, thereby allowing for a collection vehicle of substantially shortened wheelbase.
Still a further object of the invention is to provide an improved gripping apparatus which can be readily and conveniently retrofitted to a conventional prior art refuse collection vehicle.
And still a further object of the invention is the provision of improvements according to the foregoing which are expediently practiced, fabricated and maintained, in accordance with standard techniques of the art.